1. Field of the Invention
The present invention relates to an imaging device, and, more particularly, to a method of imaging substance depletion detection in an imaging device.
2. Description of the Related Art
A typical imaging device, such as an ink jet printer or electrophotographic (EP) printer, forms an image on a print medium by extracting an imaging substance, such as ink or toner, from an imaging substance reservoir and depositing the imaging substance on a surface of the print medium.
For example, an ink jet printer forms an image on a print medium by selectively ejecting ink from a plurality of ink jetting nozzles of a printhead to form a pattern of ink dots on the print medium. A color printhead may include a plurality of nozzle arrays, such as a cyan array, a magenta array, and a yellow array, arranged as a longitudinal column of nozzle arrays. A monochrome printhead may include a single monochrome nozzle array arranged as a longitudinal column. During ink jet printing, ink is supplied to the printhead from an ink reservoir, which contains an ink supply. The ink reservoir may be formed with the printhead as an integral unit, as in the case if an ink jet cartridge, or may be located remote from the printhead and fluidly coupled to the printhead via one or more ink carrying tubes. As printing occurs, ink is removed from the ink supply.
It is known in the art to attempt to detect when the ink supply is depleted. Many such attempts include the use of optical or magnetic sensors that are used to determine low levels of ink prior to exhaustion of the ink supply. However, implementation of such sensors can be difficult, and add cost to the printing system.
What is needed in the art is a method of imaging substance depletion detection in an imaging device that addresses the problems identified above.
In one form thereof, the present invention relates to a method of imaging substance depletion detection in an imaging device. The method includes the steps of identifying a theoretical coverage of an imaging substance for a first area of a sheet of print media; determining an actual coverage of the imaging substance for the first area of the sheet of print media; comparing the theoretical coverage with the actual coverage; and determining whether a depletion of the imaging substance has occurred based on a result of the comparing step.
In another form thereof, the present invention relates to an imaging system. The imaging system includes a computer. The computer includes driver software for calculating a theoretical coverage of an imaging substance for a first area of a sheet of print media. An imaging device is capable of receiving information from the computer. The imaging device is capable of performing the steps of determining an actual coverage of the imaging substance for the first area of the sheet of print media; comparing the theoretical coverage with the actual coverage; and determining whether a depletion of the imaging substance has occurred based on a result of the comparing step.
An advantage of certain embodiments of the present invention could include relatively easy implementation in any imaging device using a simple sensor that senses the presence of imaging substance on the print medium.
Another advantage of certain embodiments of the present invention is that, in an imaging device having a preexisting sensor that senses the presence of imaging substance on the print medium, for example, an embodiment of the present invention can be implemented without any additional hardware costs.